When premature babies open their eyes. Baby eyes. Why do newborns have narrow eyes. The shape of the eyes in newborns

In children born ahead of schedule, the body is not fully formed and weakened, resulting in various problems with health. Retinopathy of prematurity is one of the most common pathologies in newborns. ophthalmic disease, characterized by a violation of the structure of the vascular system of the retina. This pathological condition can cause vision loss, so it is very important to diagnose and cure the disease in time.

Retinopathy - what is it? This term refers to a severe eye disease in which there is a violation vascular structure mesh sheath. Another name for this disease is retrolental fibroplasia. In a normal state, the child's body is formed by 40 weeks of gestation. And if for some reason the baby is born earlier than the due time, then the retinal vessels remain underdeveloped.

In the first months after birth, the immature retina continues to develop, causing malformation vascular network. As a result wrong growth capillaries, pathological vessels are formed, scarring of tissues begins, provoking. Already at the beginning of the development of the pathology, the eyeballs do not distinguish light, and in the absence of timely therapy, complete loss of vision occurs. To avoid this, it is extremely important to detect signs of retinopathy in time and start effective treatment.

Causes

Retinopathy in preterm infants is a multifactorial disease that occurs under the influence of a number of factors. The main reason for the development of pathology is the prematurity of the child. And the earlier the baby was born, the higher the likelihood of a problem. Most often, retrolental fibroplasia is diagnosed in newborns born less than 32 weeks of gestation. The factors provoking the development of the disease include the following conditions:

body weight at birth less than 1500 grams;
unstable general state baby after childbirth
intracranial birth trauma;
cerebral ischemia;
birth bleeding;
sepsis;
anemia;
chronic inflammatory pathologies at mother;
genetic predisposition;
cerebral hemorrhages;
Availability concomitant diseases;
severe intrauterine infections.

Retinopathy in preterm infants can also result from excessive exposure to light on the immature retina of the newborn. Inside the mother's womb, the formation of retinal vessels occurs in the dark, and the bright light that arose at birth can cause serious disturbances.

Also, a common cause of the development of retrolental fibroplasia is oxygen therapy, during which there is an inhibition of the synthesis of glycolysis, which provides metabolic processes in the retina. Under the action of oxygen, the tissue begins to scar, the retina dies.

The risk of damage to the retinal vessels increases if mechanical ventilation is carried out for more than 3 days.

Symptoms of retinopathy of prematurity

The first symptoms of retinopathy of prematurity do not occur immediately after birth, but at about 4-8 weeks of age. It is possible to suspect the presence of the disease in premature babies by the following clinical manifestations:

low birth weight (less than 1400 grams);
unstable general condition;
the need for additional oxygen therapy.

The main manifestation of retrolental fibroplasia is the stoppage of the formation of blood vessels and the formation of new pathological capillaries that grow inside the vitreous without providing the retina with sufficient nutrition. As a result, behind the lens is formed connective tissue causing retinal detachment. During the examination, the following clinical signs are also observed:

lack of vessels on the periphery of the retina;
stagnant capillaries in the posterior pole;
poor dilation of the pupils even with the introduction of medications;
intraocular;
bilateral leukocoria.

In children under 2 years of age, retinopathy of the retina can be suspected by the following symptoms:

poor visibility of objects located at a long distance;
blinking with one organ of vision;
only one eye is involved in the visual process;
the child brings toys close to the face.

With such a disease, visual impairment is observed, the child does not notice objects located far away. Retinopathy of prematurity most often affects both organs of vision, however, the severity of the pathology in the eyes may vary. In many cases, the manifestations of the disease go unnoticed until 3-6 months of life, when irreversible changes in vision already occur.

For early diagnosis of the problem, it is necessary to regularly check with a doctor.

Stages of development

The development of retinopathy of prematurity occurs in 5 stages:

First. The part of the retina in which vessels have formed and the area without vessels are separated from each other by a line, which is commonly called a dividing or demarcation line.
Second. The dividing line becomes thicker and rougher, in its place a ridge is formed, rising above the retina.
Third. Formation process begins pathological vessels sprouting to the macular part of the eye.
Fourth. Retinal detachment begins, the vitreous becomes cloudy and scars.
Fifth. The retina is completely exfoliated, the pupil expands and acquires gray shade. There is no focusing of vision, the child does not see objects.

The first 3 degrees of development of the pathological condition are considered to be active form retinopathy, in which the child's body develops properly and the disease can disappear on its own. The fourth and fifth stages are a cicatricial form, the treatment of which can only be surgical and it does not always bring positive results. The progression of the disease occurs quite rapidly, within a few months or even weeks.

Sometimes aggressive posterior retinopathy of prematurity occurs, characterized by rapid progression and complete retinal detachment.

Diagnostics

The first examination of the child is carried out immediately after his birth. However, at this time it is almost impossible to detect pathology, so a second examination is carried out after 1-2 weeks. Starting from 3 weeks, ophthalmoscopy is performed. If there is a suspicion of retinopathy of prematurity, then an ophthalmological examination must be carried out every week until the development of grade 1 or self-regression of the disease. Ophthalmoscopy of a newborn is carried out using special drops to dilate the pupil. For staging more accurate diagnosis ultrasound of the eyeball, optical coherence tomography and diaphanoscopy.

Ultrasound diagnostics (ultrasound) of the eye.

Treatment Methods

How to treat the disease? At 1-2 degrees of development of retinopathy of prematurity, self-healing of the pathology is often observed, therefore, treatment this stage not carried out. To prevent scarring of retinal tissues, glucocorticosteroids and vitamins can be prescribed, various clinical recommendations. At stage 3, when the progression of the disease is almost irreversible, surgical intervention is necessary, which can be performed in 2 ways:

laser coagulation;
cryocoagulation of the avascular zone.

The operation will be effective only if it is carried out no later than 3 days after the detection of proliferation. Treatment of the cicatricial form of retrolental fibroplasia is also surgical treatment, but more complex - scleroplasty or vitrectomy.

Forecast and prevention

The prognosis for retinopathy of prematurity depends on many factors, so each case is different. In most cases, pathological changes undergo self-regression by 1 or 2 degrees, the child's vision is preserved. However, according to the reviews of mothers, even with such a favorable scenario, by the age of 6, various refractive deviations and other violations of the structure of the eye begin to appear. Timely diagnosis and a timely operation also allows you to restore visual functions at 3 stages. The cicatricial form of the disease carries an unfavorable prognosis, provoking development.

There is no specific prevention of retrolental fibroplasia. It is possible to prevent the occurrence of pathology only by preventing premature birth. To do this, a pregnant woman should avoid stress and overload, follow all the clinical recommendations of the attending physician.

If the baby was born prematurely, then proper nursing of premature babies and regular monitoring by an ophthalmologist is necessary.

Video about retinopathy of prematurity

From 40 to 90% of information about the world around us enters the brain through the eyes. Children with visual impairments require a special approach to develop brain function.

According to WHO, one child in the world goes blind every minute. At the same time, in 75% of cases this could have been prevented, since the child's visual apparatus develops before the age of 14. At early diagnosis many eye diseases in children are curable.

Diseases faced by pediatric ophthalmologists are most often acquired, not congenital.

Common pathologies in childhood, their photos

dry eye syndrome

Dry eye syndrome is a lack of moisture in the cornea and conjunctiva.. 50 years ago, the syndrome was considered a problem for adults, and now children also complain.

Appears due to dry air, constant eye strain, allergies, infections, anomalies in the structure of the eye.

Symptoms worse towards evening or after long exposure to wind or cold:

cutting and burning;
photophobia;
feeling of tired eyes;
the child often rubs his eyes;
complaints of blurry vision;
a network of red capillaries is visible on the protein.

Treatment - good moisturizing with drops and gels and the obligatory elimination of the causes: getting rid of the infection, changing lenses for glasses, humidified warm air. If dryness appeared due to allergies, help antihistamines.

Uveitis

Inflammation of the iris and choroid of the eye is called uveitis. It is caused by bacteria. Uveitis in children is a symptom of rheumatism, rheumatoid arthritis, glomerulonephritis, viral infection,. Because choroid The eye nourishes the retina, is responsible for its accommodation, disturbances can cause partial or complete blindness.

Rheumatic uveitis is diagnosed in children older than 3 years. It is more common in girls than in boys. The chronic form is exacerbated in spring and autumn.

The symptoms of uveitis are not noticeable at first, especially in babies who cannot talk about their feelings:

tearing;
fear of bright light;
redness of the eye;
blurred vision;
eyelid swells;
in acute form - a sharp pain.

The main symptoms of uevitis in children are shown in the photo below:

Uveitis is treated at the initial stage with anti-inflammatory drugs in the form of drops. In severe cases, injections are made into the lower eyelid, sometimes surgery is required.

Macular degeneration

Macular degeneration - dystrophic change in the retina due to insufficient nutrition. It is rare in children and may develop hereditary reasons. Macular degeneration can be dry or wet.

With dry eyes, drusen are formed - yellow pigment spots; then they merge and begin to darken.

Blackening means the death of light-sensitive cells and the development of blindness. At an early stage, it can be cured without consequences for vision.

Wet form is more dangerous. With it, new vessels appear that burst and bleed into the eye, photosensitive cells die and are not restored.

With macular degeneration, the baby complains of:

cloudy spot without pronounced contours;
disorientation in the dark;
straight lines appear curved.

Treatment of the dry form is carried out with antioxidants, preparations containing zinc, vitamins A and E. The wet form is treated with a laser, intraocular injections, and photodynamic therapy.

episcleritis

Episcleritis - inflammation of the tissue between the sclera and conjunctiva of the eye. It is rare in children. Most main symptom- Severe redness of the white of the eye. The remaining signs are common to any inflammation of the eye: swelling, photophobia, tearing, headache. A rash may appear on the face.

Episcleritis resolves on its own without treatment in 5-60 days, but can go to chronic form. Then the disease will return. Treatment is usually symptomatic: artificial tear, chamomile wash, eye rest.

Anisocoria

Anisocoria is not considered a disease, it is a symptom, in which the difference in pupil diameter in children is greater than 1 mm (as in the photo below). This is due to the fact that one of the pupils reacts incorrectly to stimuli: light, illness, medicines.

Anisocoria in a child, including a baby, may indicate:

For diagnosis, diseases are excluded from the list one by one. When the cause is eliminated, the diameter of the pupils will return to normal.

Names of common ophthalmic diseases

At birth, the eye is the least developed organ therefore, various malfunctions and dysfunctions can occur throughout the development of the visual apparatus, up to 14 years.

In addition to these diseases, ophthalmologists face other problems in children:

, or "lazy eye" A symptom in which one eye sees worse than the other. A different picture enters the child's brain, which is not processed correctly.
When the underlying disease is corrected, one eye still "out of habit" sees worse. Amblyopia is treated without consequences up to 3-4 years, while the visual areas in the brain are formed. In older children, vision will no longer be 100% the same in both eyes.
clouding of the lens, due to which the light sensitivity of the eye is lost. This disease occurs in about 3 children out of 10,000. If it is congenital, then it is diagnosed in the maternity hospital, if it develops later - at the ophthalmologist's appointment. If the cataract is not treated, then complete blindness is possible. Surgery can completely restore vision.
- infectious disease. It can be viral, bacterial or allergic in nature. It is distinguished by the appearance of purulent contents that stick together the eyelashes, redness of the eyes, a feeling of pain and "sand". Treated with antiviral or antibacterial drops depending on what caused the disease.
– bacterial inflammation hair follicle or sebaceous gland on the eyelid, not contagious, appears with a decrease in immunity. Most often affects children from 7 to 17 years. In adolescents during puberty, the secretion of the sebaceous gland becomes more viscous, it clogs the exit and causes inflammation. The disease lasts about a week and ends with the opening of the abscess.
- inflammation of the cartilage due to blockage of the sebaceous gland on the upper (more often) or lower eyelid. It is manifested by swelling and redness, then an inflamed pea appears. Most often occurs in children 5-10 years old. It is treated with massage, warming, drops. If necessary, the operation is performed under local anesthesia.
Glaucoma can be congenital and secondary, includes more than 60 diseases with a violation of the outflow of intraocular fluid. Because of this, it increases intraocular pressure leading to optic nerve atrophy and blindness. In children, it is most often congenital, after 3 years it is diagnosed very rarely. More than 50% of children who have found congenital glaucoma, without surgery, go blind by 2 years.

(myopia) is the most common eye disease in children. With this disease, the baby does not see objects located far away.
It occurs mainly in children from 9 years of age, progresses to adolescence due to rapid growth and hormonal changes.
May be due to heredity, birth defects, constant eye strain, poor nutrition. Corrected with glasses or lenses.
- Blurry vision of near objects. All children under 7-9 years old are farsighted from birth, but this figure decreases as the eye apparatus develops. If the eyeball develops incorrectly, then farsightedness does not decrease with age. Corrected by wearing glasses or lenses.
- Irregular shape of the cornea, eye or lens. Because of this, objects are seen distorted. It is treated by wearing special glasses, with the help of orthokeratology, from the age of 18 it is possible to perform a laser operation.
- violation of the patency of the lacrimal canals. Because of this, the fluid in the channel accumulates, begins purulent inflammation. It can be congenital and acquired, acute and chronic. In the acute form, a hole is formed in the corner of the eye for 2-3 days, through which the liquid breaks out.

nystagmus- inability to fix the eyeball in one position. Fluctuation can be horizontal and vertical, speaks of diseases of the nervous system.
It does not appear immediately, but closer to 2-3 months. In most children, nystagmus goes away on its own. In severe cases, surgery is indicated.
- weakness eye muscles in which the eyes look in different directions. In the first months, this is considered the norm, especially in premature babies, and then corrected by the operation.
Retinopathy of the newborn- violation of the development of the retina. Occurs in 20% of children born before 34 weeks weighing less than 2 kg due to the fact that the eyeball has not yet fully formed. About 30% of children survive this disease without consequences for their vision in the future.
The rest develop complications: myopia, astigmatism, glaucoma, cataracts, retinal detachment.
Ptosis- weakness of the muscle that lifts the upper eyelid. If this congenital anomaly, then most often it is combined with other diseases. The eye may close completely or only slightly. This feature is corrected surgically at the age of 3-4 years.

Small children can also have problems with their eyes. Therefore, articles on such topics will be useful to you:

More useful information about eye diseases learn from the following video clip:

Most eye diseases in children with early diagnosis can be successfully treated. Even developing blindness can be stopped and corrected if timely attention is paid to signs of visual impairment in a child.

In contact with

The significance of the ROP problem is determined not only by its frequency, since the disease can spontaneously regress to early stages development without serious consequences. Of great importance is the fact that ROP is characterized by a progressive course and in 5-40% of cases reaches the terminal stages. At the same time, the risk of disease progression depends not only on the degree of immaturity of the infant, but also on a number of contributing factors, nursing conditions, as well as the timeliness of the preventive treatment - medication, laser coagulation and cryosurgery. Thanks to the introduction of preventive treatment into practice, the frequency of severe forms of ROP in developed countries has decreased significantly.

There are over 50,000 blind children in the world due to retinopathy. The total number of blind children in the world is 1.4 -1.26 (1999-2010).

AT last years the frequency of preterm birth in industrialized countries and various regions of Russia ranges from 5 to 12%. According to various studies, the number of children born weighing less than 1000 g reaches 1.2%, of which 25-65% are considered viable. Proportion of children with birth weight less than 1500g. varies from 0.4 to 1.8%. In Russia, 6% of premature babies (12% in large cities).

An increase in the number of children with retinopathy of prematurity is expected in connection with the transition of Russia to the world-accepted criteria for fetal viability - a gestation period of 22 weeks and a body weight of 500 grams or more.

Advances in neonatology - an increase in the number of surviving very premature babies, and this, in turn, led to an increase in the incidence of retinopathy of prematurity, including its severe forms, in which there is a pronounced violation visual functions.

A premature baby is characterized by the risk of damage to almost all body systems; the organ of vision is also a target. In premature infants of early age, eye diseases and anomalies in the development of the organ of vision are detected 2.5-5 times more often than in those born at term.

The incidence of retinopathy of prematurity depends on many conditions (socio-economic, biological, environmental) and varies widely - from 17 to 43%, reaching 24.7 per 100,000 surviving premature babies.

ROP frequency in Russia -

0.2-0.3 per 1000 child population
24.7 per 100 thousand surviving newborns
In the ROP risk group 25-42.7%
The frequency of severe forms of ROP is 4-10% (every 10th child with ROP loses sight)

Blindness due to ROP

Developed countries - 60 per 10 million children (2007), Europe, USA - 0.2-0.3 per 1000 children.

Developing countries - 450 per 10 million children (2007), 0.7-0.9 per 1000 children.

Countries with a low level of development - no ROP (premature babies do not survive).

Risk factors

The incidence of ROP depends on the degree of prematurity, somatic burden (mother/fetus) and survival conditions (social factors). Also affected:

Multiple pregnancy, although it has been established that the incidence of retinopathy in multiple pregnancy correlates mainly with low body weight and other risk factors (hypoxia, etc.).
The condition of the mother during pregnancy, mainly her diseases that contribute to the occurrence of fetal hypoxia: chronic diseases of the female genital organs, preeclampsia, bleeding during childbirth, chronic infections, smoking, taking beta-blockers, etc.
Oxygen therapy (oxygenation mode). In fact, the intensity of oxygen therapy is largely determined by the degree of immaturity of the infant and the presence of concomitant diseases that pose a threat to life and / or lead to the development of severe hypoxia (heart disease, circulatory disease, respiratory syndrome, including pneumonia, atelectasis, etc.)
The dependence of the development of ROP on the presence of acidosis, sepsis, anemia in newborns, repeated blood transfusions, etc., has been established in premature infants.
Presence of hyperoxia and deviations in partial pressure carbon dioxide are considered important only before the age of 32 weeks, and blood transfusion and additional ventilation of the lungs - at any age.
The impact of free radicals on the membrane structures of the retina and its vessels. Exactly excessive accumulation free radicals explain the influence of such risk factors as bronchopulmonary dysplasia, necrotizing enterocolitis, intraventricular hemorrhages, respiratory distress syndrome and cardiopathy, diseases belonging to the group of so-called free radical diseases

An analysis of the intensity of oxygen therapy showed that the risk factors for the development of ROP are the stay of a child in conditions of artificial lung ventilation for more than 5 days, the duration of general oxygen therapy for more than 20 days, and the partial pressure of oxygen in the blood over 80 mm Hg.

Finishing the review various factors the risk of developing ROP, it is necessary to dwell on one more important point. J. Flynn (1992) hypothesized that ROP is genetically determined. After analyzing the nature of the course of the disease, the timing of its onset and the frequency of clinical symptoms, the author expresses the opinion that the development of ROP is associated with damage to the genetic program of retinal vasculogenesis, apparently, even in the period prenatal development, and the disease itself develops after the birth of the child.

This emphasizes the fact that the timing of the development of ROP depends not so much on the age of the child after birth, but on his gestational age: the disease begins to develop in the retina at a strictly defined time, at 32-44 weeks of gestation. The relationship with gestational age and the degree of immaturity determines the occurrence of ROP, and only then do various factors of nursing and the condition of the child come into force, which aggravate the course of the process. This hypothesis is supported by the results of the study using the methods of molecular genetics. It is known that sex-linked familial exudative vitreoretinopathy is phenotypically similar to ROP and in some cases is associated with a mutation in the Norrie disease gene. Molecular genetic studies have suggested that a mutation in the Norrie disease gene may also play a role in the development of severe forms of ROP.

ROP practically does not occur among children weighing more than 2000 and among those born after 35 weeks. gestation.

The pathogenesis of retinopathy of prematurity

Despite many years of clinical and experimental studies, the pathogenesis of ROP is not fully understood. Modern ideas about ROP are reduced to the recognition of the multifactorial nature of its origin, when many different risk factors cause a violation of normal retinal vasculogenesis in very preterm, immature infants. It is the violation of retinal vasculogenesis that underlies the development of ROP, and therefore it can rightfully be called a disease of developing retinal vessels.

In order to understand the pathogenesis of the disease, it is necessary to know the normal process of development of retinal vessels. The fetal retina is avascular up to 16 weeks of gestation. AT given period begins the growth of blood vessels from the optic disc towards the periphery. At the same time, an accumulation of spindle-shaped cells appears peripapillary in the layer of nerve fibers, which, apparently, are precursor cells of the vascular endothelium during embryonic development, although not all researchers share this point of view. The coincidence of the localization and maturation of spindle cells with the formation and growth of retinal vessels allows us to consider them as precursor cells of vessels. However, an alternative is also possible. Progenitor cells can be mesenchymal cells, while spindle cells can play the role of scaffold (glial) for growing and forming vessels.

Astrocytes also play an important role in the process of normal vascularization of the retina. They, like the vessels, are localized in the inner layers of the retina.

Migration of astrocytes from the ONH to the periphery precedes the growth of blood vessels. Astrocytes, in addition, can induce the formation of capillary-like structures from the endothelium in cell culture. During vasculogenesis, spindle cells migrate to the periphery through retinal cystic spaces formed by Müller cells. Migrating spindle-shaped cells are interconnected and form, as it were, a crescent, facing the dentate line.

Forming accumulations at the border of the vascular and avascular retina, they gradually transform into capillary endothelium. The process of growth and formation of blood vessels is regulated by a number of mediators. These include vascular endothelial growth factor (VEGF), fibroblast growth factor, insulin-like growth factor, etc. The most studied effect of VEGF, which is produced by various cell lines under hypoxic conditions and is necessary for the growth of embryonic vessels and normal vasculogenesis.

In the retina, VEGF is produced by astrocytes and Müller cells. It is proposed to distinguish two types of formation (development) of blood vessels:

Type 1 - from progenitor cells, this process is commonly called vasculogenesis.
2nd type - from pre-existing, formed vessels, or angiogenesis.

In ROP, both of these mechanisms appear to be at work.

Premature baby is born with incomplete retinal vascularization, accumulation of spindle-shaped cells on the border of the vascular and avascular zones. After premature birth, the child goes from intrauterine hypoxia to relative hyperoxia of the normal air environment or receives additional oxygen, which may be the basis for a violation of normal retinal vasculogenesis. Various pathogenetic mechanisms of this process are considered.

Previously, it was believed that the direct damaging effect of excess oxygen on the vascular endothelium plays a leading role in the pathogenesis of ROP. The resulting vasoobliteration leads to retinal hypoxia and subsequent abnormal angiogenesis.

An experimental study of the role of oxygen in the development of a disease similar to ROP in newborn puppies and kittens made it possible to hypothesize about the predominant role of oxygen in the development of the disease during the change in hyperoxia/hypoxia phases. According to this hypothesis, the vasoconstrictor effect of hyperoxygenation causes narrowing of the lumen of the capillaries, which, with prolonged hyperoxia, leads to desolation and obliteration of the vessels.

When animals get into normal conditions, i.e. under conditions of relative hypoxia, endothelial proliferation and growth of newly formed vessels with the formation of proliferative tissue occur.

One of the mechanisms of ROP pathogenesis is the effect of free radicals on the membrane structures of the retina and its vessels. Reduced ability of preterm infants to resist free radicals causes intense peroxidation of plasma membranes and damage to spindle cells. This, in turn, leads to the activation of the formation of massive intercellular connections between spindle cells, disruption of their normal migration and the process of vasculogenesis. Instead, they are activated to form the rough endoplasmic reticulum.

In addition, activated spindle cells under conditions of retinal ischemia secrete an angiogenic factor that causes vascular proliferation.

It is important to emphasize that, unlike other proliferative diseases (eg, diabetes), in which vessels grow in the zone of vitreous detachment, with ROP, vessels grow directly into the vitreous. Proliferation of vascular and glial tissue causes tractional retinal detachment.

In this case, the traction goes in the anterior direction, which determines the characteristic shape of the detachment - funnel-shaped. In the process of development and progression of ROP, the structure of the vitreous body itself changes significantly, and zones of liquefaction and voids form in it. In addition, proliferative tissue is formed in the area of the optic disc, which contributes to the narrowing and rapid closure of the posterior portion of the "funnel".

This most popular hypothesis of ROP pathogenesis explains many of the clinical manifestations of ROP and justifies the need for preventive treatment. According to this hypothesis, it is immaturity that is the key to the development of ROP, since at normal birth dates there are practically no undifferentiated spindle cells or other vascular progenitor cells in the retina.

In recent years, interesting studies have been carried out on animal models to study the role of VEGF in the pathogenesis of ROP. The obtained new data made it possible to formulate a hypothesis explaining the pathogenesis of ROP mainly by VEGF dysregulation.

When a baby is born prematurely, there is a sudden rise in oxygen levels in the retina. This relative hyperoxia causes a decrease in VEGF production and thus inhibits normal growth vessels, and also leads to vasoobliteration of existing vessels. An increase in tissue metabolism during the development of the retina and an increase in hypoxia in the peripheral, avascular portions of the retina cause hyperproduction of VEGF, which leads to abnormal neovascularization. In this case, glial cells can work as oxygen "sensors", although it is not yet clear how this happens.

One of contentious issues The pathogenesis of ROP is the analysis of the causes of the development of a pathological reaction of immature vessels to hyperoxia. The reason may be that vasoconstrictor mechanisms develop earlier than dilator ones, which leads to vascular imbalance.

According to another point of view, vasoconstriction is protective. So, R. Flower et al. (1990) showed that inhibition of prostaglandin synthesis reduces the degree of vasoconstriction in hyperoxic neonatal animals, but they develop more severe forms of the disease.

The role of superoxide dismutase deficiency in the development of vascular disorders in the retina of newborn animals under conditions of hyperoxia is currently being studied in an animal model.

The role of hypercarbia (increased carbon dioxide content in the blood) in the pathogenesis of ROP is discussed. Experimental data have been obtained that isolated hypercarbia (without hyperoxygenation) can lead to the development of retinal neovascularization in newborn rat pups.

Histological data on the development of degeneration of retinal astrocytes under the influence of excess oxygen were obtained. It has also been suggested that the accumulation of protein substances in the vitreous body and the disruption of the hyaloid circulation lead to the development of neovascularization, which was shown in the model of newborn animals.

However, with all the variety of pathogenetic mechanisms, one of the main risk factors for the development of ROP is the deep immaturity of the fetus and eye tissues by the time of premature birth. It is well established that the highest risk of developing ROP and, in particular, its severe forms in children with lower birth weight and lower gestational age.

The results of studies conducted in recent years indicate that the development of ROP is influenced not so much by the hyperoxia factor as by fluctuations in the partial tension of oxygen and carbon dioxide in arterial blood. So, in experimental studies on newborn animals, it was found that the development of neovascularization and retinopathy in them occurs when exposed to normobaric or hypobaric oxygen. An increase in oxygen concentration is accompanied by a vasoconstrictor effect on the vessels of the choroid, resulting in a decrease in oxygen transport to the inner layers of the retina during hyperoxygenation of the animal. Under conditions of hyperbaric hyperoxygenation, vasoconstriction occurs, which is accompanied by tissue hypoxia during the transition of the animal to normal conditions. This in turn is accompanied by vasoproliferation. The results of experimental studies made it possible to approach the solution of the issue of optimizing oxygen therapy in premature infants. In particular, it is proposed to additionally carry out oxygen therapy during the progression of retinopathy in order to prevent the onset of the threshold stage of the disease. However, comparative studies of the ROP frequency with constant and variable oxygen supply did not reveal differences in the comparison groups.

One of the mechanisms of ROP pathogenesis is the effect of free radicals on the membrane structures of the retina and its vessels. It is the excessive accumulation of free radicals that explains the influence of such risk factors as bronchopulmonary dysplasia, necrotizing enterocolitis, intraventricular hemorrhages, respiratory distress syndrome and cardiopathy, diseases belonging to the group of so-called free radical diseases.

Given the hypothesis of a crucial role of free radicals in the development of ROP, an attempt was made to use antioxidants for the prevention and treatment of ROP. However, the use of alpha-tocopherol in the clinic has not received convincing data on its activity. However, after a period of skepticism about the use of antioxidants, interest in them has risen again in recent years. This is due to the detection of vitamin E deficiency in the blood serum of premature infants. In connection with the establishment of a close relationship between the antioxidant systems of mother and child, it is recommended that pregnant women use an "antioxidant cocktail" (containing vitamin E and selenium) as a means of preventing the development of ROP in risk groups.

The point of view is controversial, according to which the presence of hyperbilirubinemia is important in the development of ROP. Along with indications of its role as one of the risk factors, there is an opinion about the protective role of hyperbilirubinemia.

An important issue of the ROP problem is the assessment of the role of light exposure on the onset and course of the disease. Under natural conditions, retinal vasculogenesis is completed during fetal development in the absence of any light exposure. A premature baby gets into unnatural lighting conditions for him, including excessive, associated with the need to care for the child, as well as an ophthalmological examination. Naturally, taking into account the known data on the damaging effect of light on the retina, the question of the influence of this factor on the immature retina is especially relevant. However, in numerous studies devoted to the study of this issue, no convincing evidence was obtained of the influence of the duration of exposure and the degree of illumination on the incidence and severity of ROP.

Clinical picture and course

The basis of the clinical manifestations of ROP is a violation of retinal vasculogenesis, which begins at the 16th week of intrauterine development and ends only by the time of the birth of the child (40 weeks). Almost all premature babies have ophthalmoscopic differences from full-term babies.

In the fundus of preterm infants (normal), avascular zones are always detected on the periphery of the retina, and their length is the greater, the lower the gestational age of the child at the time of examination. The presence of avascular zones on the periphery of the fundus is not a manifestation of ROP, but only evidence of underdevelopment of the retina, incompleteness of vasculogenesis and, accordingly, the possibility of developing retinopathy in the future.

In its development, the disease goes through several stages, reflecting the progression of the active process. The active ROP is replaced by the stage of regression, and then - the cicatricial stage of the disease.

The activity, extent and localization of the process can vary significantly. In 1984, in Canada, ophthalmologists from 11 leading countries of the world developed the International Classification of Active Retinopathy of Prematurity and a single registration form pathological changes in the eye. This classification, with minor clarifications and additions, is used everywhere to this day.

According to the international classification, active ROP is subdivided depending on the stage of the process, its localization and extent.

Stage I - the appearance of a demarcation line at the border of the vascular and avascular retina. The whitish line is located in the plane of the retina and histologically represents an accumulation of hyperplastic spindle-shaped cells. The region of the posterior pole of the eye can be practically unchanged. Occasionally, tortuosity and vasodilatation in the area of the optic nerve head (OND) are noted. On the periphery of the fundus, in front of the line, the vessels, on the contrary, are, as a rule, dilated and tortuous, can form abnormal branching, vascular arcades, suddenly break off, without penetrating into the avascular retina beyond the line.
Stage II - the appearance of a rampart (or ridge) at the site of the demarcation line. The retina in this zone thickens and protrudes into the vitreous, resulting in the formation of a yellowish shaft. Sometimes it looks hyperemic due to the penetration of blood vessels into it. The vessels of the retina in front of the shaft, as a rule, are sharply dilated, tortuous, randomly divide and form arteriovenous shunts, a kind of "brush" at the ends of the vessels. The retina in this zone is edematous, and perifocal edema of the vitreous body may also appear. More often than in stage I, nonspecific changes in the peripapillary zone are also detected in the form of edema and vascular disorders. Histologically, the process is spindle cell hyperplasia with proliferation of endothelial cells.

In stages I-II, in 70-80% of patients with ROP, spontaneous regression of the disease is possible with minimal residual changes in the fundus.

Stage III characterized by the appearance of extraretinal fibrovascular proliferation in the area of the shaft. At the same time, vascular activity in the posterior pole of the eye increases, exudation into the vitreous body increases, arteriovenous shunts on the periphery become more powerful, forming extended arcades and plexuses. Extraretinal proliferation may be in the form of delicate fibers with vessels or dense tissue located outside the retina posterior to the shaft.

With a small prevalence of the process (1-2-hour meridian), as well as in the first two stages, spontaneous regression is possible, but the residual changes are more pronounced.

The development of an extraretinal process on 5 consecutive or 8 total hourly meridians is considered to be the threshold stage of ROP, when the process of ROP progression becomes almost irreversible. Some experts suggest subdividing stage III ROP into mild (IIIa), moderate (IIIc), and severe (IIIe) depending on the extent of extraretinal proliferation.

Stage IV - partial retinal detachment. Retinal detachment in active retinopathy is exudative-traction in nature. It arises due to both the serous-hemorrhagic component and the emerging traction from the newly formed fibrovascular tissue.

IVa (no macular involvement)
IVb (with retinal detachment in the macula).

Stage V - complete, or total, retinal detachment. Due to the characteristic localization of the newly formed fibrovascular tissue (anterior to the equator), as well as the pronounced destruction of the vitreous body, the appearance of cavities and voids in it, retinal detachment, as a rule, has a "funnel-shaped" shape. It is customary to distinguish between open, semi-closed and closed forms of funnel-shaped retinal detachment. With a narrow and closed profile of funnel-shaped retinal detachment, there is a pronounced cellular proliferation between the sheets of the retina, their fusion.
Microscopically, degeneration of the outer and inner layers of photoreceptors and superficial gliosis are isolated in the detached retina.

Stages IV and V ROP are usually called terminal due to poor prognosis and severe visual impairment.

The subdivision of the process according to the extent and localization matters practically only for the first three stages of the disease.

The spread of the pathological process in the fundus is assessed by hourly meridians (from 1 to 12). And according to the localization of RN, there are three zones

Zone 1 is a conditional circle centered on the optic disc and with a radius equal to twice the disk-macula distance.
Zone 2 - a ring located more peripherally than the 1st zone, with an outer border passing along a dentate line in the nasal segment.
Zone 3 - a crescent on the temporal periphery, outward from zone 2.

ROP in zone 1 is much more severe and has a worse prognosis.

A prognostically unfavorable form of active ROP, called " plus-disease". It is characterized by early onset and rapid progression. As a rule, zone 1 is involved in the process, i.e. posterior pole of the eye. "Plus-disease" proceeds with more pronounced activity, which is manifested by a sharp sharp expansion of the retinal vessels, their tortuosity, the formation of powerful vascular arcades on the periphery, hemorrhages and exudative reactions. This form of ROP is accompanied by pupillary rigidity, iris neovascularization, exudation into the vitreous body, which makes a detailed examination of the fundus very difficult.

Due to the rapid course of ROP and the ineffectiveness of generally accepted preventive measures, the terminal stages of the disease develop.

The duration of the active stages of ROP, or rather active ROP, is on average 3-6 months. It ends either with spontaneous spontaneous regression in the first two stages of the disease, or with a scarring phase with residual changes in the fundus of varying severity, up to total retinal detachment.

There is no single classification of cicatricial stages of ROP. However, the International Committee for the Classification of ROP (1987) gave recommendations for evaluating the results of examinations of children with regressive and cicatricial stages of the disease. It is recommended to analyze both changes in the retina itself and its vessels in the periphery of the fundus and in the region of the posterior pole.

Vascular changes include:

incomplete vascularization of the retina in the periphery,
the presence of pathological and abnormal branching of blood vessels,
formation of arcades, arteriovenous shunts, telangiectasias, etc.

In the region of the posterior pole, a displacement of the great vessels, their tortuosity, a change (decrease) in the angle of the vessels' discharge during dichotomous branching, etc. can be detected.

Retinal changes include

redistribution of pigment
areas of retinal atrophy,
formation of pre-, sub- and intraretinal membranes, ruptures and thinning of the retina
in severe cases, traction deformity of the optic disc develops,
ectopia and macular deformities,
crescent-shaped folds of the retina are formed,
traction retinal detachment.

For the V regressive stage of ROP, in addition, changes in the anterior segment of the eye are characteristic:

swelling and clouding of the cornea,
small anterior chamber
posterior and anterior synechiae,
entropion of the iris and its atrophy,
development of angle-closure glaucoma,
clouding of the lens, etc.

I degree - the presence of minimal vascular and intraretinal changes in the periphery of the fundus, which practically do not affect visual functions;
II degree - macular ectopia and vitreoretinal dystrophic changes on the periphery, which can subsequently lead to the development of secondary retinal detachments;
III degree - gross deformation of the optic disc with severe ectopia and dystrophy of the macular region in combination with the above-described changes in the periphery of the fundus;
IV degree - the presence of rough sickle-shaped folds of the retina, causing significant visual impairment;
Grade V - total funnel-shaped retinal detachment of an open, semi-open or closed type.

In contrast to stage V of active ROP, retinal detachment in cicatricial ROP always has a traction character.

If with active ROP the process is more often bilateral and rather symmetrical, then with cicatricial ROP it can be asymmetric in 20-30% of cases. The reasons for the different course of ROP in paired eyes have not been established.

Diagnostics

Examination of a premature baby for retinopathy begins at 32-34 weeks of development (usually 3-4 weeks after birth). Further, ophthalmologists examine the baby every 2 weeks until the completion of vascularization (formation of retinal vessels). When the first signs of retinopathy appear, the examination is carried out weekly until the complete regression of the disease or the activity of the process subsides. With "plus-disease" - 1 time in 3 days.

The fundus examination is carried out using indirect binocular ophthalmoscopy. Inspection is carried out with the obligatory expansion of the pupil and the use of special children's eyelids. The first examination is usually carried out in the neonatal intensive care unit under the control of monitors.

Additionally, for the diagnosis and monitoring of the effectiveness of treatment, ultrasound procedure.

For differential diagnosis between retinopathy and other diseases, causing violation functions of the visual analyzer in premature babies - partial atrophy of the optic nerve, anomalies in the development of the optic nerve, etc., registration of visual evoked potentials (VEP), electroretinogram (ERG) is used.

In case of regression of retinopathy of newborns, a child should be examined by an ophthalmologist once every 6-12 months up to 18 years - to exclude complications associated with retinopathy (in particular, retinal detachment in adolescence).

Differential Diagnosis

Subject to the rules and conditions of the examination, taking into account the knowledge of the clinical manifestations of ROP, differential diagnosis in the active stages of the disease does not cause significant difficulties.

"Plus disease" must be differentiated from retinoblastoma . Changes in the ONH apart from the characteristic peripheral manifestations of ROP can be mistakenly regarded as manifestations of intracranial hypertension and various pathological conditions of the central nervous system with the development congestive optic disc. It is necessary to differentiate ROP from retinal hemorrhages of newborns, which, as a rule, manifest themselves in the early stages after childbirth with their complicated course. They are also often detected in full-term babies, large fetuses, and prolonged labor.

Great difficulties arise in the differential diagnosis of cicatricial stages of ROP, especially in cases where an ophthalmologist first examines a child at a late age.

The most difficult to differentiate ROP (with the formation of sickle-shaped folds and atypical bands) from primary persistent hyperplastic vitreous(PPST). When conducting differential diagnosis, it is necessary to pay attention to the unilateral lesion in PPST, its often observed combination with anomalies of the anterior segment of the eye, as well as the absence of changes in the fellow eye. It is also necessary to keep in mind the possibility of combining RN with PPST.

Clinical manifestations similar to the symptoms of ROP can be observed with peripheral uveitis, X-linked retinoschisis, Eales' disease, Wagner's vitreoretinal degeneration etc. However, based on the results of a thorough analysis of anamnestic data and clinical manifestations of the disease, in the vast majority of cases, it is possible to establish the correct diagnosis.

Almost indistinguishable clinical manifestations of ROP and familial exudative vitreoretinopathy - slowly progressing bilateral disease with a pronounced family character. The timing of its manifestation varies, but the disease always develops at an older age and is not related to prematurity.

Surgery

Surgical treatment of patients with ROP is divided into preventive and rehabilitation. The first group includes cryotherapy and laser coagulation (transscleral and transpupillary), as well as some methods of scleral depression at the stage of disease progression.

Rehabilitative surgery includes predominantly produced lensvitrectomy, less often isolated excision of membranes in the vitreous body (lens-sparing surgery), as well as various methods scleral depression. Of particular note are organ-preserving surgical operations that are performed in the terminal stages of the disease in order to prevent secondary complications (corneal clouding, development of angle-closure glaucoma, etc.)

Currently, the effectiveness of prophylactic laser and cryocoagulation of the avascular retina is considered to be proven - interventions that can reduce the incidence of adverse disease outcomes by 30-50%.

In 1988, the first results of the work of the joint group were published, in particular, recommendations to be sure to carry out procedures in all cases of the development of the so-called threshold stage of active ROP, involving zones 2 and 3 in the process. 5 hour meridians in a row or 8 hour meridians in total. In addition, it was proposed to consider all processes localized in zone 1 of the fundus or proceeding as a "plus disease" as an indication for cryocoagulation. Long-term studies to evaluate the effectiveness of prophylactic cryocoagulation in ROP have made it possible to convincingly prove the feasibility of its implementation, as well as to identify the range of possible complications and contraindications for use. this method treatment.

Complications of cryocogulation are edema, maceration and chemosis of the conjunctiva, subconjunctival hemorrhages up to hematomas, increased IOP, vitreal and retinal hemorrhages, occlusion of the central retinal artery, the formation of proliferative membranes, damage to the muscles of the eyeball, and with a rough procedure, even its perforation. As a rule, the causes of such complications are errors in the treatment. It should be emphasized that the discussion on the choice of methodology and timing of the procedure, evaluation of treatment results continues to this day. Most ophthalmologists coagulate only the avascular retina behind the shaft, i.e. ahead of him. However, there are recommendations to coagulate also the area of the shaft itself and extraretinal tissue growth.

Cryocoagulation technique

As a rule, transconjunctival coagulation is performed, and only when the process is localized in zone 1 does it become necessary to make an incision in the conjunctiva concentrically to the limbus or between the rectus muscles. Coagulates are applied under the control of an ophthalmoscope with a special cryo-tip intended for the treatment of ROP, and in its absence, with standard retinal or cataract tips. The average exposure time is 2-3 s when opening the conjunctiva, 2-6 s when using the transconjunctival technique. Coagulates are applied from the dentate line towards the posterior pole of the eye, concentric to the limbus.

Treatment is often carried out under anesthesia (to avoid oculocardial and oculopulmonary reactions), less commonly used local anesthesia although there is no consensus on this issue. Evaluation of the results of treatment should be carried out after 7-10 days. If necessary, the procedure can be repeated.

The efficiency of cryocoagulation ranges from 50 to 79% according to different authors. The effectiveness of treatment largely depends on the extent and localization of the lesion, as well as the presence of "plus disease".

Most pronounced therapeutic effect achieved when performing coagulation in patients with ROP in stage IIIa. Subsequently, myofibroblasts migrate from the shaft into the vitreous body and cause traction retinal detachment even with complete destruction of ischemic zones. Based on this, F. Kretzer and H. Hittner (1988) recommend that the shaft be exposed at the final stage of coagulation.

laser photocoagulation, proposed for the treatment of ROP as early as 1968, was then pushed into the background by cryotherapy. This was due to a number of technical difficulties in its use in preterm infants.

In recent years, due to the widespread introduction into clinical practice of an indirect binocular ophthalmoscope (NBO) for argon laser coagulation, the technique has again been actively used in ROP. It has been shown that in terms of efficiency it is at least not inferior to cryocoagulation, and possibly even surpasses it.

Method of laser photocoagulation

Currently, an argon blue-green laser with a wavelength of 488-514.5 nm and a diode laser with a wavelength of 810-814 nm are used for the treatment of ROP, both predominantly through the NBO system. The advantage of laser coagulation over cryocoagulation is that the effect laser radiation limited mainly to the inner plexiform layer of the retina and pigment epithelium, there is no effect on the sclera. In addition, laser coagulation makes it possible to successfully treat a disease localized in zone 1. However, the procedure is very difficult for a rigid pupil, it takes more time due to the relatively small size of coagulates (400-600 microns).

As with cryotherapy, during laser coagulation, the avascular retina is exposed anterior to the shaft, although there are recommendations to coagulate the area of arteriovenous shunts. Coagulates are applied close to each other, and their number reaches 250-2500. Average power 350-600 mV, exposure time 0.2-1 s. As a result, the procedure is very lengthy; 15-45 minutes are spent on laser coagulation of one eye. Due to the significant duration of the procedure, the problem of anesthesia is very relevant. Opinions on this subject are contradictory, although most ophthalmologists prefer general anesthesia.

A decrease in vascular activity in the posterior pole of the eye occurs on the 3rd-7th day, and regression of extraretinal proliferation occurs on the 10th-14th day. The expediency of drug treatment in the postoperative period is not recognized by all ophthalmologists. More often, instillations of corticosteroid drugs are used to reduce edema and vascular reactions. In recent years, there has been a trend towards the use of additional oxygen therapy both after cryo- or laser coagulation, and in cases of progression of the process in order to reduce the degree of retinal hypoxia, although the issue of dosages, timing and effectiveness remains controversial and requires further study.

Efficiency laser treatment at RN it reaches 73-90%. A comparative study of the results of using argon and diode lasers showed that, despite the different technical specifications(wavelength), the results of their application are almost the same and comparable to the results of cryotherapy. The effectiveness of treatment largely depends on the time of the procedure (threshold or pre-threshold stage), as well as the severity and localization of the pathological process. The results of treatment of ROP in the posterior localization (zone 1) are significantly worse than with the development of the process in zones 2 and 3, although they exceed those with cryocoagulation. Thus, satisfactory results of cryotherapy with posterior and anterior forms of ROP were obtained in 40 and 94% of cases, respectively, and with laser coagulation - in 88 and 98%.

Complications of laser coagulation in ROP are keratopathy, corneal and lens burns, hyphema, and retinal hemorrhages. The appearance of cataracts on the 14-99th day after the procedure is described.

The advantage of the diode laser over the argon one is the lower frequency of damage to the anterior lens capsule, especially in the presence of the pupillary membrane. In addition, this type of laser is more transportable and can be used directly in intensive care units for premature babies.

Special attention should be paid to possible complications anesthesia, which include cyanosis, bradycardia, arrhythmia, transient hypertension, etc.

Despite certain disadvantages, laser photocoagulation is currently the treatment of choice for ROP prophylactic treatment. Its advantage over cryocoagulation lies in the possibility of a better dosing of the degree of coagulation and the formation of more tender scars in the retina, a lower incidence of eye complications, greater possibilities in the treatment of zone 1, as well as the transportability of the system with the possibility of treatment in neonatology departments.

Used in a number of institutions, transscleral laser coagulation techniques for the treatment of ROP do not have significant advantages over transscleral cryocoagulation.

With the ineffectiveness or insufficient effectiveness of preventive treatment, as well as in the absence of it, a number of infants develop severe cicatricial forms of the disease. The possibility and expediency of performing one or another type of surgical intervention in order to eliminate the consequences of ROP or improve (at least partial) visual functions are determined by the specific clinical manifestations of the disease.

With partial retinal detachments (stage IV) or mild forms of stage V, operations of scleral depression of various lengths (filling, circular depression) and shortening of the sclera can be performed.

In patients with stage V ROP, in the presence of a funnel-shaped retinal detachment of a traction nature, lensvitrectomy open or closed type. In both cases, the removal of the lens is a necessary part of the surgical intervention due to the need to excise fibrous tissue in the retrolens space, often fixed to the ciliary processes. The trend towards lens-sparing vitrectomy for ROP, which has emerged in recent years, is very important, since the state of aphakia significantly complicates the process of vision development after successful surgical interventions. However, this is only possible with limited retinal detachments, without fixing the folds to the posterior surface of the lens.

The timing of lensvitrectomy for cicatricial ROP varies widely. In all cases, it is not advisable to perform the operation earlier than 6 months due to the high risk of reproliferation and hemorrhagic complications due to the presence of residual vascular activity. With a delay in the implementation of surgical intervention, the chances of a functional result of the operation are reduced. However, experienced surgeons often recommend surgery at the age of 8-12 months, and in the absence of preventive treatment - not earlier than 12 months.

A positive anatomical result (attachment or partial attachment of the retina) when performing one or a series of surgical interventions (additional circular suture, additional excision of membranes with the introduction of silicone, etc.) is achieved in 45-64% of patients with cicatricial forms of ROP.

Differences in the effectiveness of the intervention are due to the different initial state of the eyes and the timing of the operation. So, with funnel-shaped retinal detachment of a closed and narrow type, the efficiency decreases to 11-32% Best Results obtained with PH stage IV, as well as with an "open" type of funnel in the case of an early operation.

The functional results of surgical interventions leave much to be desired. After lensvitrectomy, visual acuity rarely exceeds 0.01. In most cases, the nature of light perception, light projection only improves, the ability to track objects near the face and the possibility of orientation in the room appear. The ratio of the frequency of anatomical and functional positive effect in stages IV and V of ROP ranges from 64 and 43% (respectively) according to different authors: in stage V 40 and 16%.

The results of open vitrectomy in stage V ROP, according to T. Hirose et al. (1993), - 58 and 32%, respectively. In the late period after surgery, the anatomical effect may decrease due to reproliferation and the appearance of retinal breaks, while the functional effect depends on a complex of factors, including methods for correcting aphakia and the intensity of pleoptic treatment.

Early correction of aphakia and active pleoptic treatment are among the most important factors in obtaining a satisfactory functional result. Contact correction gives the best results.

Visual acuity and refraction in children with ROP

Visual functions in children with ROP depend on a complex of factors.

First of all, they are defined severity of PH and the nature of residual changes in the fundus, refractive disorders, as well as the presence concomitant pathology CNS.
Neurological disorders(various hypoxic encephalopathies, leukomalacia, cerebral hemorrhages, intracranial hypertension, etc.) are often found in very premature babies. Severe violations The central nervous system can lead to visual impairment due to damage to the code and subcortical visual centers and pathways.

Delayed development of the child due to the complex neurological abnormalities also affects the development of vision at an early age. Nevertheless, when comparing long-term functional results in preterm infants with various degrees of cerebral disorders, no direct correlations were found, which can be explained by the high plasticity of the functions of the cortex and other brain structures in the neonatal period.

The determining factor in the development of visual acuity in preterm infants with ROP is the state of the posterior pole of the eye and directly the macular area of the retina. The spectrum of changes in this area of the fundus in regressive ROP includes hypoplasia and dystrophic changes in the macula of varying severity (from mild pigment redistribution to intraretinal membrane formation).

In the presence of extraretinal proliferation on the temporal periphery, as a rule, deformation and ectopia of the macula are detected, and in more severe cases, the so-called "crescent" retinal folds, which cause a significant decrease in vision.

In addition, there are data on the presence of retanal dysfunction in children who have undergone mild forms of stages I-II of ROP, without residual visible changes on the fundus. This was evidenced by violations of the ERG parameters and oscillatory potentials.

An important factor affecting the development of vision in preterm infants are refractive errors. It is generally accepted that preterm infants with ROP are at high risk early development myopia. The mechanism by which myopia develops in preterm infants is unclear. There are attempts to explain its appearance by the peculiarities of the anatomical and optical parameters of the eye - the growth of the predominantly anterior segment, the anterior position of the lens, its large volume and sphericity, and the greater curvature of the cornea. Nevertheless, there are no clear ideas about the mechanism of development of myopia in ROP. It is only known that myopia of prematurity is characterized by early start, a smaller size of the anteroposterior axis of the eye, a greater curvature of the cornea and a more spherical lens compared to the anatomical parameters of the eyes with myopia of another origin.

According to one point of view, myopia is a normal refraction of premature babies and, as a transient condition, is observed in more than half of premature babies in the early periods of life. It has been established that the value of refraction in a premature baby changes with age, myopia is formed mainly in the range of 3-12 months and then stabilizes by 12-24 months.

In addition to myopia, preterm infants with ROP often develop astigmatism and anisometropia, which can also be an important factor in visual impairment. Thus, a thorough study of refraction and correction of ametropia are important factors in the development of visual functions in children with ROP.

In addition to refractive disorders, children with ROP often (up to 23-47%) have strabismus of various origins - refractive, anisometropic, paretic, as well as false or secondary, associated with macular ectopia.

When assessing the state of visual functions and the visual analyzer in premature babies, it is necessary to take into account the timing and sequence of their development. It is known that the potentials of the retina and cerebral cortex develop very rapidly in children during the first 4 months of life. Developmental processes in the visual system include photoreceptor and foveal differentiation, optic nerve myelination, maturation of the lateral geniculate body, and development of visual fields in the cerebral cortex. At the same time, stabilization of visual functions occurs by 2-6 years.

In the absence of neurological and eye pathology The development of visual functions in premature babies occurs much faster than in full-term ones. In this case, it is necessary to evaluate the adjusted age of the infant, taking into account the timing of prematurity.

Visual acuity in infants is assessed using orientation tests (tracking objects at different distances) and various variations of the preferred gaze technique (using specially designed maps, gratings and stripes on the monitor screen). Studies have shown that most children with ROP I-II stages visual acuity corresponds to healthy infants (visual acuity is affected by strabismus, amblyopia, brain disorders). A clear dependence of visual acuity on residual changes in the fundus (the degree of macular ectopia, dystrophic changes, etc.) was revealed. Visual acuity in ROP III-IVa stages varies from 20/200 to 20/3200.

Line of sight. A group of researchers conducted a comparative analysis of the state of the monocular visual field in premature infants with a birth weight of less than 1251 g without ROP and with stage III ROP. The studies were carried out at the age of 5.5 years by the method of kinetic perimetry (double-arc) with a mark size of 6 o. The results were evaluated by 4 main meridians (upper and lower temporal, upper and lower nasal). A significant narrowing of the visual field in the eyes of patients who underwent the threshold stage of ROP was revealed, compared with the control group.

In addition, a comparative study of the visual field in the eyes of patients with ROP in the threshold stage and without it (according to 8 meridians), conducted in a group of older children (6-11 years old), revealed a slight additional narrowing of the visual field after cryotherapy.

18-11-2013, 01:28

Description

2-6

Postnatal development of the visual system goes in two directions: the first is the development of neurons to provide contrast, orientation, color, direction of movement, size and depth of the image (parvocellular pathway), the second is the formation of mechanisms that control eye movement, which is necessary for the subject perception of the world and drawing attention to this or that or to another object (magnocellular pathway).

Data have been obtained, according to which premature infants without ROP, although they do not differ from term infants of the corresponding age in visual acuity and stereoperception, have reduced contrast sensitivity and impaired color perception, which confirms the hypothesis of high risk damage to the "immature" visual system of premature babies. Pathology of color vision in preterm infants indicates impaired function of retinal cones, and a decrease in contrast sensitivity can be explained by a smaller number of functioning rods.

The determining factor in the development of visual acuity in premature infants with ROP is the condition of the posterior pole of the eye and directly the macular area of the retina. The spectrum of changes in this area of the fundus in regressive ROP includes both macular hypoplasia and macular dystrophic changes of varying severity: from gentle pigment redistribution to intraretinal membrane formation. In the presence of extraretinal proliferation on the temporal periphery, as a rule, deformities and ectopia of the macula are detected, and in more severe cases, the so-called sickle-shaped folds of the retina, which cause a significant decrease in vision.

The results of electrophysiological studies of newborns indicate that the visual pathways and the retina are already functioning at the time of birth. During the neonatal period, both cortical and retinal responses change very rapidly, demonstrating the process of maturation of the visual system, especially in the first four months of life. AT histological studies it was found that the process of maturation includes elongation of the outer segments of rods and cones, differentiation of the foveola, thickening of the myelin sheath of the optic fibers and pathways, an increase in the number of dendritic processes, proliferation of synaptic connections in the outer geniculate body and visual cortex, as well as an increase in the cortical volume of primary and secondary visual areas.

Research using the latest technologies and computer analysis revealed weak cone and rod responses of the retina even in preterm infants, starting from 34 th week of gestational (from conception) age. G. Horslen et al. (1962) when recording an ERG with electrodes on a contact lens after 15 -minute dark new adaptation revealed a scotopic b-wave with an amplitude of 40 to HO μV in the first days of life of newborns. The rod-cone mediated response matures relatively quickly in the first 3 months after birth, then slows down somewhat and to 12 month, the ERG amplitude is about 10 % ERG adults.

Examining the ERG of infants different ages, A. Fulton and R. Hansen (1985) found smaller maximum amplitudes of a- and b-waves in newborns, and also found that a relatively large light load is required to obtain half the amplitude.

I. Grose et al. (1989) surveyed 30 premature babies in the intensive care unit and found that among premature babies up to 35 weeks of gestational age, there is a tendency to deformation (expansion and flattening) of b-waves and a relative weakening (decrease in amplitude) of a-waves. Between 30 -th and 50 th weeks of gestation is a linear "maturation" of the ERG. A linear correlation has been established for both the amplitude and latency of the b-wave with age: the amplitude increases by 3 μV per week, and the latency decreases by about 0,8 MS per week. To 3-4 month b-wave reaches 80 mkV (in adults 300 µV), in 6 a month, an a-wave appears, the light rhythm is reproduced, and only by the year the child's ERG corresponds in shape to the adult's ERG.

In premature babies for the first months of life, the latency of ERG waves is longer and the amplitude is lower than in full-term babies of the same age. At 6 months of corrected age, the ERG parameters of term and preterm infants are almost identical.

When evaluating the results of VIZ registration for an outbreak or pattern, age parameters must be taken into account. It is known that outbreak VEPs are registered in newborns of the first days of life, and in premature babies 22-27 weeks of gestational age, only negative activity is determined, on 250-300 ms, and to 30-35 weeks a positive response appears with latency 190-230 ms. The fastest (with the speed 10 ms per week), the latency of the positive component decreases in the range from 30 before 50 weeks of gestational age, and to 4 months it is only 5 ms more than in full-term children of the same age.

Comparative assessment of the development of vision in healthy preterm infants and in the presence of pathology, carried out by A. Norcia et al. (1987), showed that in healthy preterm and full-term children, the VEP indicators do not differ significantly. This suggested that VEP visual acuity develops from the moment of birth and does not depend on the timing of pregnancy. Although the question of whether it is necessary to focus on the corrected age of the child when assessing LLL indicators is widely discussed in the specialized literature, no convincing answers have yet been received. The sweep-VEP technique has proved to be quite demonstrative in the assessment of visual functions in children who lack fixation and tracking, or in those who, due to behavioral reactions, the study of vision by other methods is not possible. VEP and visual acuity, reflecting mainly the functions central departments retina, highest value have been tested for "mild" forms of ROP.

Pattern-VEP in children aged 6- 9 weeks are registered only for patterns with a large cell size ( 220-55 ). In the interval from 6-9 before 16- 20 weeks, a reaction to smaller cells appears, the configuration of the VEP becomes more complicated, their amplitude increases, and the latency decreases. To 24 weeks begin to register VEP for cells of small sizes. After 6-7 month, the rate of VEP “maturation” decreases, and by 6-7 years VEP in configuration and amplitude-age characteristics approach the response of healthy adults.

An important role in the development of vision in children with ROP is played by concomitant neurological pathology. Neurological disorders are often observed in very preterm infants and include various hypoxic encephalopathies, leukomalacia, cerebral hemorrhages, intracranial hypertension, etc. Severe disorders of the central nervous system can lead to visual impairment due to damage to the cortical and subcortical visual centers and pathways. The developmental delay of the child, accompanied by a complex of neurological abnormalities, also affects the development of vision at an early age. However, when comparing long-term functional results in preterm infants with cerebral disorders No direct correlations of varying severity were found, which can be explained by the significant plasticity of the functions of the cortex and other brain structures in the neonatal period.

If the baby is born prematurely - up to 37 weeks of pregnancy He is considered premature.

There are several degrees of prematurity in newborns. Light, as a rule, does not pose a danger to the health of the baby, heavy - requires serious medical care.

Mild prematurity

If the baby is born between 32 and 36 weeks of pregnancy, modern medical care allows him to avoid health problems.

Breast milk for premature babies

Full breastfeeding is not always available. For example, premature babies usually do not have sucking reflex- They are fed through a tube. It does not necessarily transfer the baby to artificial feeding. Pumping is the way out.

In some cases, children with mild degree Prematurity does not have time to fully mature lungs. They need additional help with breathing: artificial ventilation of the lungs or additional oxygen supply in the first days of life.

Many babies with mild prematurity have feeding problems. Babies born before 34–35 weeks are unable to suckle on their own and must be fed with a tube.

Therefore, babies born at this time are forced to stay in the children's department of a hospital or maternity hospital for several more weeks until they can start feeding on their own.

In addition, within a few weeks, all premature babies may experience problems with maintaining body temperature. In this case, they are left couveze- a special box for newborns - to maintain optimal temperature and monitor cardiac activity and respiration.

In the future, after discharge, parents should carefully monitor the child's body temperature. It is easy for premature babies to overheat or catch a cold.

Average degree of prematurity

The baby is born into the world at 28-31 weeks of gestation. In children born at this time, the lungs are not yet fully ripe for breathing. Typically, they require assistance in the form of mechanical ventilation or a constant flow of oxygen-enriched air to maintain positive airway pressure.

Most children with medium degree prematurity, such assistance is required for a fairly short time.

If the child is on artificial lung ventilation, he is fed through intravenous catheter. Children who breathe on their own can feed on mother's milk through a tube until they learn to suck on their own.

Severe prematurity

The baby is born before the 28th week of pregnancy. Previously, such children survived extremely rarely, but modern medicine allows you to nurse such babies.

Almost all children born at this time have not yet developed lungs - most of them require mechanical ventilation or oxygen-enriched air flow.

The lungs can maintain respiratory function from 22–24 weeks of fetal development, but the alveoli necessary for normal oxygen uptake do not develop until 28–30 weeks of gestation.

In addition, severely premature babies cannot feed themselves and maintain body temperature. Parents of such babies need to understand that the child stay in the children's department for a long time.

Why is it dangerous for children to be born before term?

Babies who were born before the 37th week of pregnancy may have problems associated not only with the lack of a sucking reflex.

The shorter the period at which the child was born, the higher the risk of developing various diseases characteristic of premature babies.

underdeveloped lungs

Pulmonary disorders are the most dangerous. For example, neonatal difficulty breathing syndrome, in which the immature lungs of the baby cannot fully crack down. For a breath the child should make considerable efforts.

These children need artificial respiration support.

Respiratory arrest

In premature babies, the respiratory center of the brain is not yet fully formed. If a person does not breathe often enough, the command from the brainstem compensates by breathing deeper.

Newborn babies, on the other hand, breathe shallowly and irregularly, and they have periods of too slow breathing. If they occur too often, doctors talk about development of respiratory arrest, or apnea.

Nine month

While you are expecting a baby, planning repairs in the nursery and buying everything you need, your child is growing and developing. Find out, how does the baby live during those nine months.

A baby with such a disorder needs constant monitoring in the first weeks of life. As the child grows, the risk of sleep apnea decreases.

Features of the heart

During fetal development, the child's blood practically does not pass through his lungs due to the structural features of the heart. The heart of the embryo pushes blood from the right ventricle not into the pulmonary artery, but into the aorta through an opening called the ductus arteriosus.

Shortly after birth, in full-term babies, it overgrows, and in premature babies, it may remain open. It leads to increased load to the lungs and heart. This condition requires medical or even surgical treatment.

Infections, metabolic problems and blindness

Infections affect premature babies more often than babies born at term. One reason for this vulnerability is immaturityimmune system , in which antibodies in the blood of the child are produced in insufficient quantities.

Also dangerous for premature babies are viral infections, which cause only mild cold symptoms in other babies.

In addition, premature babies may have problems with absorption of nutrients, as well as a lack of hemoglobin associated with a low rate of formation of red blood cells - erythrocytes.

Premature babies can also develop retinal damage - retinopathy of prematurity without early treatment leading to blindness.

That is why premature babies should remain under the supervision of neonatologists from birth until the moment when their body is ready for independent living.

The most important

A child born even before the 28th week of pregnancy can not only survive, but over time catch up with full-term babies in development.

All premature babies require careful care and supervision of doctors in order to avoid diseases caused by the immaturity of their body.

Common problems in premature newborns:

the greater the degree of prematurity, the worse the respiratory, swallowing, sucking skills are developed in the crumbs. It is very difficult for such children to survive without an incubator.

babies who are premature do not have the necessary fat layer, and in this regard, it is very difficult for them to maintain their body temperature, so it is very important to prevent hypothermia. If it suddenly happens that the baby’s temperature drops below 32 degrees, he will immediately be sent to an incubator or to his mother on her tummy. At the same time, the temperature will be measured 4-5 times per hour. Until she returns to normal, the baby will be in special conditions.

one of the most terrible and dangerous problems with prematurity is that when small weight episodes of hypoglycemia may occur. That is, if the baby's blood falls glucose level, then phenomena such as difficulty breathing, convulsions, sleep disturbances can occur, which can even lead to lethargy.

Such a disease is treated by introducing crumbs of additional gluten into the body in order to raise its level to the required norm.

Having learned about all these consequences, we can conclude that a premature baby needs careful care, love, tenderness and warmth, like no other baby. Read more: http://www.happy-giraffe.ru/community/3/forum/post/6079/

The main problems and complications of premature babies

So, premature babies are born with underdeveloped organs and systems that are not yet adapted to function outside the womb. Against this background, any complications almost always develop.

Breath

From 28 weeks to 36 weeks, a substance called surfactant. It is it that is responsible for ensuring that the alveoli (vesicles in the lungs) do not fall down when breathing, and the lungs can function normally. If the baby appeared before 28 weeks, then he has to make great efforts in order to breathe. Therefore, artificial lung ventilation devices are often used until the moment when the child begins to cope with this task on his own.

In addition, surfactant preparations are administered to the child, helping the lungs to “ripen” and adapt to independent work.

If your baby has been connected to a ventilator, you should keep in mind that when oxygen is given, the baby's lungs get something like a burn. Unfortunately, this is inevitable, without the device, the child simply will not be able to breathe.

Such a "burn" leads to bronchospasm and increased secretion of mucus. In medicine, this condition is called bronchopulmonary dysplasia. Over time, the state of the respiratory system normalizes, however, in the future, with any infection affecting the respiratory tract, for example, SARS, it is not necessary, but it is likely that the baby will have some consequences. Namely, an increase in mucus production and bronchospasm.

In order to avoid complications up to the development bronchial asthma, you should definitely tell the pediatrician that the baby was connected to a respirator. In this case, the doctor will take measures to prevent the occurrence of spasms or treat them at an early stage.

Among other complications of the respiratory system in premature babies, the following occur.

Respiratory failure syndrome. In fact, this is the reason why babies are connected to a ventilator (artificial lung ventilation) if there is not enough surfactant yet.

Apnea. This term characterizes the condition of the newborn, in which his breathing is irregular. In this case, certain drugs are introduced or the baby is connected to a ventilator.

Heart

When a baby develops and grows in the mother's tummy, its blood flow practically does not touch the lungs, the heart sends blood to the aorta, and not to the pulmonary artery, as in an adult. Blood enters the aorta through an opening called the ductus arteriosus.

In full-term babies, this hole closes up shortly after birth; in premature babies, this may not happen. Pathology is treated with medication, much less often - by surgical intervention.

Immunity

Immunity in premature babies is also underdeveloped and cannot cope with various infections, so these babies very often get sick immediately after birth. An infection that may cause only subtle symptoms of a cold in a full-term baby is likely to manifest itself in full force in a premature baby.

It is noteworthy that babies born at 7 months of pregnancy have stronger immunity than those who were born at eight months.

Brain

The vessels of the brain in premature babies are very thin and fragile. In this regard, it is possible hemorrhages varying degrees of severity. As a rule, the earlier the child was born, the more likely extensive hemorrhages.

Why is it dangerous? Small hemorrhages can go completely unnoticed, but quite extensive ones threaten the development of such pathologies as cerebral palsy, epilepsy, learning difficulties and perception of information in the future.

If bleeding in the brain has opened, then it is quite difficult to stop it, sometimes a blood transfusion or artificial ventilation of the lungs is performed. Due to the possibility of hemorrhage, premature babies are under the control of neonatologists, and periodically undergo ultrasound of the brain.

Vision

Often, babies born prematurely are diagnosed with retinopathy premature. This phenomenon is a violation in the development of the retina.

The retina is the thinnest tissue that, let's say, captures an image in order to transmit it to the brain. In preterm infants, the retinal blood vessels may not develop properly, leading to scar tissue and, as a result, severe visual impairment.

In this case, as well as with other complications, the earlier the child was born, the greater the likelihood of developing retinopathy in premature baby.

Moderate retinopathy, fortunately, has almost no effect on the state of vision in the future. In especially severe cases, treatment is carried out with a laser or cryotherapy (treatment with cold exposure).

Why does retinopathy occur? There is no exact answer to this question, but most experts are inclined to believe that high oxygen concentrations are the cause. Therefore, this indicator is carefully monitored. In addition, premature babies are periodically examined by an ophthalmologist in order to detect deviations in time.

Intestines

Sometimes babies born prematurely develop necrotizing enterocolitis A disease in which intestinal cells die.

It is difficult to say what exactly leads to this disease, it is possible that bacterial infections play an important role.

One way or another, babies with these diseases are transferred to droppers with nutrient solutions instead of regular feedings, which reduces the burden on the digestive system. Sometimes surgery is required to remove areas of the intestine that have undergone significant destruction.

Blood

Often found in preterm infants low blood sugar. Otherwise, this phenomenon is called hypoglycemia. The treatment is additional “supplementation” with glucose intravenously or through the mouth.

There is a specific anemia of prematurity. This pathology is characterized by the fact that the baby's body is not yet able to produce enough red blood cells. In addition, the cause of anemia can be a large blood loss. Anemia in premature babies is treated with drugs or, in severe cases, blood transfusions.

If a premature baby has any of these complications, then he and his mother will have to spend a long time in the hospital, possibly several weeks. When the baby recovers a little, he will be transferred to the children's hospital.

As a rule, the mother is also admitted to the hospital so that she can take care of her child, but if the situation in the hospital is tense in terms of an overabundance of patients, then the mother may be refused. In this case, she will have to express milk daily and bring it for feedings.